Conditional maximum likelihood identification for state space system

Luo Xiao, Harutoshi Ogai, Wang Jianhong*, Ricardo A.Ramirez Mendoza

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


In this paper, we investigate the use of conditional maximum likelihood identification in the context of identifying one general state space system, being parametrized by one unknown parameter vector. The process of modifying the common state space system into our general form is presented, and the traditional negative log-likelihood function for identifying unknown parameter vector is constructed with only observed output variables. To combine state variables and output variables simultaneously, the conditional maximum likelihood estimate based on the conditional probability density and the total probability theorem is proposed here. Further, when the prior distribution of that parameter vector is flat, we continue to obtain the joint maximum a posteriori estimate. To maximize a negative log-likelihood function, the classical Robbins- Monro algorithm from stochastic approximation theory is applied to avoid the computation of the second-order derivative of conditional likelihood function.

Original languageEnglish
Pages (from-to)1-8
Number of pages8
JournalMechatronic Systems and Control
Issue number1
Publication statusPublished - 2021 Jan 27


  • A posteriori estimate
  • Conditional maximum likelihood
  • Robbins-Monro algorithm
  • State space system

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Computer Science Applications


Dive into the research topics of 'Conditional maximum likelihood identification for state space system'. Together they form a unique fingerprint.

Cite this